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Phosphate-based glasses (PBGs) in the CaO–Na2O–P2O5 system have diverse applications as biomaterials due to their unique dissolution properties. A reactive force field (ReaxFF) has been developed to simulate these materials at the atomic level. The ReaxFF parameters of PBGs, including the interaction between phosphorus and calcium atoms, have been developed using a published code based on genetic algorithms. The training data, including the atomic charges, atomic forces, bond and angle parameters, and different differential energies, are chosen and measured from static quantum-mechanical calculations and ab initio molecular dynamics of PBGs. We did different short- and medium-range structural analyses on the bulk simulated PBGs with different compositions to validate the developed potential. Radial and angular distribution functions and coordination numbers of network formers and modifiers, as well as the network connectivity of the glass, are in agreement with experimental and previous simulations using both shell-model classical force fields and ab initio simulated data; for example, the coordination number of phosphorus is 4.0. This successful development of ReaxFF parameters being able to describe the bulk PBGs enables us to work on the dissolution behavior of the glasses, including the interaction of water molecules with PBGs, in future works. [ABSTRACT FROM AUTHOR]

Inert ceramic implants suffer from significant complications such as lack of osseointegration, biofilm formation, and infections, necessitating the development of novel materials with both osteogenic and antibacterial properties to prevent implant failure. In this study, we aimed to multifunctionalize a tridimensional macroporous alumina scaffold with a biomimetic calcium phosphate (CaP) coating combined with a silver-based extra-thin film to enhance bioactivity and provide an additional antibacterial effect. The porous alumina scaffolds were fabricated through a powder metallurgy technique, followed by biomimetic deposition and DC magnetron sputtering. The coatings were characterized using SEM/EDS and AFM measurements to examine their morphology and topography. To evaluate the osteoconductive response of the materials, in vitro tests were conducted by immersing the samples in Simulated Body Fluid (SBF). The bioactivity tests revealed that the CaP-AgO coating, in line with the roughness surface and free surface energy values, exhibited a higher Ca/P ratio formation. This indicated an increased affinity for apatite adhesion, ultimately leading to a higher osseointegration ability compared to the CaP-Ag coating. Furthermore, the CaP-AgO coating demonstrated superior activity against S. aureus. These findings demonstrate the potential of the multifunctional coatings to address the challenges associated with inert ceramic implants by promoting bioactivity and combating bacterial infections. [ABSTRACT FROM AUTHOR]

The current work focuses on developing 40B 2 O 3 -(20- X)Li 2 O-15P 2 O 5 -20CaO- X ZrO 2 (X = 0, 1 and 2 mol %) bioactive nano glasses by a novel microemulsion method and conducting in-vitro studies. CaO derived from fresh water snail shells has been used to produce cost effective glasses. DTA, FTIR, XRD, FESEM, degradation, pH, BET and cell viability tests have been carried out for these glasses. The glasses show good bioactivity and cell viability. ZrO 2 reduces the formation of hydroxyapatite and decreases cell viability. The role of ZrO 2 on the glass structure and in-vitro properties has been clearly discussed. [ABSTRACT FROM AUTHOR]

Uncontrolled acute and persistent bleeding, as well as with infection, is a great challenge because of the high mortality during treating the patients with injuries, complex surgery or bone marrow failure. Here, we develop an external form of natural components which is based on phosphorylated methacrylated gelatin (GelMA, G) cryogel (GP) loaded with tannic acid (TA)-mixed copper ion (Cu2+) mesoporous bioactive glasses (MBG), named after GP@MBG-Cu-TA cryogel, to address the goals of reduce persistent bleeding and enhance antibacterial activity. Structurally, GP@MBG-Cu-TA cryogel is based on GP, MBG loaded with TA and Cu2+ adheres to GP via hydrogen bonding. In vitro, GP@MBG-Cu-TA cryogel displays a good biocompatibility, hemostatic and antimicrobial capability. In vivo studies, GP@MBG-Cu-TA cryogel can enhance the hemostatic effect in the liver injury in SD rats for the acute bleeding, as well as in the aplastic anemia and hemophilia A mice with tail amputation for the persistent bleeding. In addition, GP@MBG-Cu-TA cryogel accelerates the skin wound repair in the mice with the bacterial contamination at the injury site. In sum, GP@MBG-Cu-TA cryogel is not only endowed with dual function of hemostatic and antimicrobial capability, but also can stop bleeding of the objects with either normal or abnormal coagulation function. Thus, GP@MBG-Cu-TA cryogel provides a promising candidate dressing for managing bleeding and bacterial complications in clinic. [ABSTRACT FROM AUTHOR]

Shape memory polymers (SMPs) and their composites (SMPCs) have emerged as popular materials in a variety of industries due to their unique properties of shape-changing behavior in response to external stimuli. The inclusion of reinforcement may modify the SMPs to enhance their thermal and shape memory properties. Different types of bio ceramics have already been used to alter the thermal and shape memory behavior of SMPs. However, using bioactive glass (BG) as filler to modify these properties has not yet been explored. Despite the significant advantages that shape-memory polymers (SMPs) offer when combined with 3D/4D printing technology, their potential in 3D printing has been explored only to a limited extent. This work created a solvent-based 4D-printed temperature-sensitive shape memory polymer composites (SMPCs) system using polylactic acid (PLA) and bioactive glass (BG). The influence of BG on the thermal as well as shape-memory capabilities of composites was further examined. An increase in the degree of crystallinity and viscoelastic characteristics of PLA/BG composites led to improved shape memory properties, like shape fixity and shape recovery. These findings suggest the potential for using the developed SMPC printed through 4D printing technology, to develop complex shapes for self-foldable structures and smart biomedical devices in the future. [ABSTRACT FROM AUTHOR]

In the context of 4D printing, the term "fourth dimension" pertains to the capacity of materials to change their shape or form once they have been manufactured. This characteristic enables them to possess enhanced functional capabilities and enables the creation of applications that prioritize performance. Stimulus-responsive materials like shape memory polymers provide great opportunities to be used in 4D printing for a wide range of applications. Using polylactic acid (PLA) and bioactive glass (BG), this study demonstrates the developed material's potential for processing and experimentation for shape memory properties and 4D printing. Expanding our approach, a multi-objective optimization was done to minimize shrinkage and maximize strength along with shape recovery for 4D printed shape memory polymer composites (SMPCs) with the help of the central composite design (CCD) approach commonly referred to as response surface methodology (RSM). The model was validated by conducting confirmation tests using the best possible combination of parameters for the process, as determined utilizing the genetic algorithm multi-objective optimization method. In the end, different structures were developed by utilizing 4D printing at optimum parameters and the shape-changing behavior was recorded in the 4D printed parts by applying a thermal stimulus. [ABSTRACT FROM AUTHOR]

(1) Background: The onset of inflammation and oxidative stress after biomaterial implantation can lead to complications and prolonged recovery times. To address this, bioactive mesoporous glasses doped with cerium (0, 3.6 and 5.3 mol%) were loaded with three different biomolecules—3-hydroxyflavone, quercetin and morin hydrate—to enhance antioxidant properties while preserving bioactivity. (2) Methods: Elemental analysis, specific surface area determination, spectroscopic techniques, evaluation of antioxidant activity and in vitro bioactivity assessment were performed to characterize mesoporous glass loaded with biomolecules. (3) Results: Biomolecule loading gives values in the range of 0.5–2.0% and 10.3–39.6% for loading content and loading efficiency, respectively. The loading order is quercetin > morine hydrate > 3-hydroxyflavone, and a cerium percentage of 3.6 seems to be a good compromise. The antioxidant properties evaluated on both solids and solutions in contact with simulated biological fluids improve markedly over loaded glasses, and the most promising results are obtained with quercetin. In the most efficient systems, the bioactivity results were delayed and more evident at longer times (168 h) but were still retained. (4) Conclusions: We obtained new materials still bioactive with improved antioxidant properties that can be proposed for the regeneration of both hard and soft tissues. [ABSTRACT FROM AUTHOR]

Objective The mechanism of the odontogenic differentiation of apical papillary cells (APCs) stimulated by bioactive glass 45S5 is still unclear. This study aims to investigate the effect of autophagy on the odontogenic differentiation of APCs stimulated by bioactive glass 45S5. Methods APCs were isolated and cultured in vitro, and the cell origin was identified by flow cytometry. The culture medium was prepared with 1 mg/mL 45S5, and its pH and ion concentration were determined. The experiments were divided into control, 45S5, and 3-methyladenine (3-MA) 45S5 groups. In the 45S5 group, APCs were induced to culture with 1 mg/mL 45S5. In the 3-MA 45S5 group, the autophagy inhibitor 3-MA was added to 1 mg/mL 45S5. Protein immunoblotting assay (Western blot) was used to detect the expression of autophagy-associated proteins of microtubuleassociated protein 1 light-chain 3β (LC3B) and P62 after 24 h of induction culture in each group. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of bone sialoprotein (BSP), Runt-related transcription factor 2 (Runx2), dentin sialophosphoprotein (DSPP), and dentin matrix protein-1 (DMP-1) after 7 d of induction culture. Cellular alkaline phosphatase (ALP) staining analyzed cellular ALP activity at 7 d of induction, and alizarin red staining evaluated the formation of mineralized nodules at 21 d of induction. Results The pH of the 45S5 extract culture medium was 8.65±0.01, which was not significantly different from that of the control group (P>0.05). The silicon ion concentration of the 45S5 induction culture medium was (1.56±0.07) mmol/L, which was higher than that of the control group (0.08±0.01) mmol/L (P<0.05). The calcium ion concentration of the 45S5 induction culture was (1.57±0.15) mmol/L, which was not significantly different from that of the control group (P>0.05). Western blot results showed that LC3B- II/I ratio increased and P62 expression decreased in the 45S5 group compared with those in the control group (P<0.05). By contrast, the ratio decreased and the expression increased in the 3-MA 45S5 group compared with those in the 45S5 group (P<0.05). RT-qPCR results showed that the expression of BSP, Runx2, DMP-1, and DSPP enhanced in the 45S5 group compared with that in the control group (P<0.05), but the expression decreased in the 3-MA 45S5 group compared with that in the 45S5 group (P<0.05). Semi-quantitative analysis of ALP staining and alizarin red staining showed that the ALP activity was enhanced, and the formation mineralized nodule increased in the 45S5 group compared with those in the control group. The ALP activity weakened, and the formation mineralized nodules were reduced in the 3-MA 45S5 group compared with that those in the 45S5 group. Conclusion Cell autophagy participates in the odontogenic differentiation of APCs induced by 1 mg/mL 45S5 in vitro. [ABSTRACT FROM AUTHOR]

Introducing therapeutic ions of bioactive glasses as scaffolds is appealing due to attractive architectural biomimicry of bone extracellular matrix and adjustable composition accompanied with soluble ions released for bone regeneration and remodeling. Herein, this strategy was expanded to develop biocomposites of borosilicate glasses incorporated with different therapeutic ions using a facile sol-gel technique and cetyltrimethylammonium bromide (CTAB) as the template. Mediating therapeutic ions (i.e. , copper/selenium/strontium at the same content) in a SiO 2 –B 2 O 3 –CaO–P 2 O 5 glassy system is effective and simple method for modifying structural-morphological features and physicochemical characteristics of the bioglasses. In vitro bioactivity measurements revealed that strontium/selenium-doped borosilicate glasses had faster apatite-formation ability compared to copper-doped borosilicate glasses. For in vitro drug release, rhodamine B (RB) storage and release showed that copper-doped borosilicate glasses had high storage capacities (79.42 %) and cumulated release rate (87.18 % at pH 1.2), and demonstrated sustained pH-sensitive drug release patterns. The RB release profiles also showed two-stage release mechanism following the Korsmeyer-Peppas model during the first release stage (the first 24 h), and the Weibull model during next stage (beyond 24 h). In subsequent bacterial studies, copper-doped borosilicate glasses could effectively inhibit (100 % at 2.5 mg mL−1) Escherichia coli and Staphylococcus aureus colonization. In vitro biocompatibility assays also showed that all bioglass samples were biocompatible. According to obtained data, present bicomponent composite strategy may pave the way for the design of bioglasses doped with functional ions tailored to induce biological activity that can heal infectious bone in vivo. [Display omitted] • Se-58S30B and Sr-58S30B exhibited the enhanced in vitro bioactivity. • Cu-58S30B has superior drug delivery ability and antibacterial effect. • Non-linear kinetic models fit better for Rhodamine B staged release from all bioglass nanosphere. [ABSTRACT FROM AUTHOR]

Macrophage metabolism is closely linked to their phenotype and function, which is why there is growing interest in studying the metabolic reprogramming of macrophages. Bioactive glass (BG) S53P4 is a bioactive material used especially in bone applications. Additionally, BG S53P4 has been shown to affect macrophages, but the mechanisms through which the possible immunomodulatory effects are conveyed remain unclear. According to the results presented here, the lipopolysaccharide (LPS) induced suppression in oxidative phosphorylation is rescued in macrophages cultured with BG S53P4 before the inflammatory stimulus. Additionally, BG S53P4-exposed macrophages expressed lower mRNA levels of inflammatory cytokines Il6 and Il1b, as well as demonstrated decreased activation of inflammatory interferon regulatory factor (IRF) and NF-κB pathways and nitrogen oxide secretion in response to LPS. These results did not rely on cells being in direct contact with the material as similar effects were observed in the presence of BG S53P4-conditioned medium. Our findings link the immunomodulatory properties of BG S53P4 and macrophage metabolism, which improves our understanding of the mechanisms underlying the clinical efficacy of bioactive glasses. [ABSTRACT FROM AUTHOR]

The escalating burden of nosocomial infections presents a formidable challenge to healthcare systems worldwide, leading to increased morbidity, prolonged hospital stays, and elevated healthcare costs. These infections are often resistant to conventional antibiotic therapies due to their association with biofilms which contribute to the persistence and resistance of pathogens. In addressing the challenge of biofilm-associated nosocomial infections, borate bioactive glasses (BBGs) have emerged as promising biomaterials. Doping these glasses with antimicrobial metals could potentially harness their antibacterial properties to prevent biofilm formation. This study undertakes a rigorous evaluation of the anti-biofilm efficacy of copper and zinc-doped BBGs by employing processed imaging techniques and machine learning algorithms that allow for the in-depth analysis of biofilms. The study focused on three bacterial species known for their prevalence in nosocomial infections and propensity to form biofilms: Staphylococcus epidermidis , Escherichia coli , and Pseudomonas aeruginosa. Results indicated a marked reduction in biofilm viability and morphological disruptions upon treatment with copper and zinc-doped BBGs, highlighting their potential as a novel approach to combatting the persistent challenge of nosocomial infections. The persistent challenge of nosocomial infections within healthcare facilities underscores a pressing need for innovative strategies aimed at mitigating the risk and spread of these infections. Nosocomial infections not only result in significant morbidity and mortality among patients but also impose a heavy financial burden on healthcare systems due to increased treatment costs and extended hospital stays. The complexity of combating these infections is further compounded by the biofilm-forming capabilities of many pathogenic bacteria, which can adhere to a wide range of surfaces, including medical devices and surgical equipment. In this context, the development and application of copper and zinc-doped BBGs (Cu/Zn-BBGs) represent a novel and promising approach to preventing biofilm-associated nosocomial infections. The incorporation of antimicrobial metal ions into the BBG matrix offers a dual-functional strategy: enhancing the inherent bioactive properties of the glasses while introducing potent antimicrobial activity against biofilms. This innovative approach lies on the gradual and complete release of copper and zinc ions from the BBG into the surrounding environment, targeting biofilms at their initial formation stages and disrupting their development. The antimicrobial mechanism of these metal ions, which includes disruption of bacterial cell walls, alteration of DNA replication, and inhibition of metabolic processes, provides broad-spectrum activity against a variety of pathogens that cause nosocomial infections. The novelty of this research also lies in its methodological approach, particularly the use of processed microscopic images for the detailed analysis of the anti-biofilm effectiveness of the BBGs. Confocal laser scanning microscopy (CLSM) image analysis is a pivotal tool used in this study, allowing for the in-depth visualization and quantitative analysis of biofilm structures. CLSM's capability to produce high-resolution, three-dimensional images of biofilms in situ enables the precise assessment of the antibiofilm efficacy of Cu/Zn-BBGs. Moreover, using scanning electron microscopy (SEM) for both qualitative and quantitative analysis provided pivotal information on the biofilms' structural characteristics and surface interaction. [ABSTRACT FROM AUTHOR]

Bone is a natural mineral-organic nanocomposite protecting internal organs and allowing mobility. Through the ages, numerous strategies have been developed for repairing bone defects and fixing fractures. Several generations of bone repair biomaterials have been proposed, either based on metals, ceramics, glasses, or polymers, depending on the clinical need, the maturity of technologies, and knowledge of the natural constitution of the bone tissue to be repaired. The global trend in bone implant research is shifting toward osteointegrative, bioactive and possibly stimuli-responsive biomaterials and, where possible, resorbable implants that actively promote the regeneration of natural bone tissue. In this mini-review, the fundamentals of bone healing materials and clinical challenges are summarized and commented on with regard to progressing scientific discoveries. The main types of bone-healing materials are then reviewed, and their specific relevance to the field is reminded, with the citation of reference works. In the final part, we highlight the promise of hybrid organic-inorganic bioactive materials and the ongoing research activities toward the development of multifunctional or stimuli-responsive implants. This contribution is expected to serve as a commented introduction to the ever-progressing field of bone regeneration and highlight trends of future-oriented research. [ABSTRACT FROM AUTHOR]

Phosphate invert glasses (PIGs) exhibit excellent biocompatibility because of their high chemical durability and controlled ion releasability. PIGs are composed of short phosphate units such as ortho‐ and pyrophosphate. This structure makes it difficult to obtain clear glass using the melt‐quenching method. Our previous work reported that intermediate oxides (such as TiO2 and Nb2O5)‐containing PIGs exhibit good glass‐forming ability and ion dissolution controllability. This work used a liquid‐phase method to prepare PIGs at room temperature and pressure. Furthermore, TiO2 was used to control ion releasability for biomedical applications. Titanium‐containing PIGs were successfully prepared using a liquid‐phase method. Pyrophosphate and titania formed P‐O‐Ti bonds with an increasing TiO2 content in the glass, forming chain‐like structural units such as (‐O‐P‐O‐P‐O‐Ti‐O‐)n. The number of chain‐like structures increased with an increasing TiO2 content in the glass, improving the chemical durability. Hence, the ion releasability of titanium‐containing PIGs prepared using the liquid‐phase method can be controlled by the glass structure. Additionally, the PIGs exhibited good cell viability. Therefore, the PIGs are candidates for carriers of therapeutic inorganic ions for biomedical applications. [ABSTRACT FROM AUTHOR]

Phosphate invert glasses (PIGs) have been attracting attention as materials for bone repair. PIGs have a high flexibility in chemical composition because they are composed of orthophosphate and pyrophosphate and can easily incorporate various ions in their glass networks. In our previous work, incorporation of niobium (Nb) into melt-quench-derived PIGs was effective in terms of controlling their ion release, and Nb ions promoted the activity of osteoblast-like cells. In the present work, a liquid-phase method was used for synthesizing Nb-containing PIGs, as this method allows us to prepare a glass precursor solution at room temperature, which can be attributed to improved glass-shape design. Nb-containing PIGs were successfully prepared, and their ion release behavior was controlled by changing the Nb content in the PIGs. The functions of Nb varied according to its content. For example, in the case of PIGs containing a larger amount of Nb, Nb acted as both the network modifier and former while also inducing the formation of chain-like structures. These glasses possessed a gradual ion release in a tris-HCl buffer solution. Cotton-wool-like structured scaffolds were fabricated using the synthesized Nb-containing glass using a wet-spinning method. Because the scaffolds possess excellent flexibility and controllable ion release, they are good candidates for new biomaterials. [ABSTRACT FROM AUTHOR]

Background: CaO-SiO2-P2O5-B2O3 bioactive glass-ceramics7 (BGS-7) are known for their strong integration with bone and stability and are commonly used in spinal fusions. Purpose: This study aimed to compare fusion rates and radiological and clinical outcomes between BGS-7 and allograft spacers with iliac bone grafts (IBG) in multilevel anterior cervical discectomy and fusion (ACDF) surgeries. Study design/setting: This retrospective study was conducted at BRM Medical Center. Patient sample: We included patients who underwent multilevel ACDF at BRM Medical Center between January 2012 and December 2023. The patients had symptoms such as cervical radiculopathy and myelopathy due to cervical disc herniation, stenosis, and spondylosis. Outcome measures: We evaluated the preoperative and postoperative Japanese Orthopedic Association (JOA) scores, neck disability index (NDI), functional rating index (FRI), and visual analog scale (VAS) scores for the neck, shoulder, and upper extremities at 6 months and 1 year after surgery. Methods: Fusion rates were assessed using dynamic radiography and computed tomography (CT) scans at 1 year postoperatively. Radiological measurements were obtained from preoperative and postoperative plain radiographs. Results: At the 1-year follow-up, the fusion rates were 89.5% for BGS-7 and 92.2% for the allograft cage on dynamic radiographs (p=0.156) and 93.4% and 90.4%, respectively, on CT scans (p=0.319), confirming both internal and external osseointegration. Subsidence rates were 4% for BGS-7 and 10% for the allograft spacer group. Both groups showed increased cervical lordosis (CL), segmental lordosis (SL), and segmental height postoperatively, with maintained lower segmental height (LSH) in the BGS-7 group than in the allograft spacer group at postoperatively 1 year. No adjacent segmental disease (ASD) occurred in either group. The JOA, NDI, and FRI showed significant improvements in both groups. The VAS scores decreased significantly in both groups, indicating improved clinical outcomes. Conclusions: In multilevel ACDF, BGS-7 demonstrated fusion rates comparable to those of the allograft spacer with IBG, experiencing fewer instances of subsidence and cage fracture. Therefore, BGS-7 spacer can be safely utilized in multilevel ACDF as a substitute for traditional allograft spacers, without the need for additional IBG. [ABSTRACT FROM AUTHOR]

We engineered a microfluidic platform to study the effects of bioactive glass nanoparticles (BGNs) on cell viability under static culture. We incorporated different concentrations of BGNs (1%, 2%, and 3% w/v) in collagen hydrogel (with a concentration of 3.0 mg/mL). The microfluidic chip's dimensions were optimized through fluid flow and mass transfer simulations. Collagen type I extracted from rat tail tendons was used as the main material, and BGNs synthesized by the sol–gel method were used to enhance the mechanical properties of the hydrogel. The extracted collagen was characterized using FTIR and SDS-PAGE, and BGNs were analyzed using XRD, FTIR, DLS, and FE-SEM/EDX. The structure of the collagen-BGNs hydrogels was examined using SEM, and their mechanical properties were determined using rheological analysis. The cytotoxicity of BGNs was assessed using the MTT assay, and the viability of fibroblast (L929) cells encapsulated in the collagen-BGNs hydrogel inside the microfluidic device was assessed using a live/dead assay. Based on all these test results, the L929 cells showed high cell viability in vitro and promising microenvironment mimicry in a microfluidic device. Collagen3-BGNs3 (Collagen 3 mg/mL + BGNs 3% (w/v)) was chosen as the most suitable sample for further research on a microfluidic platform. [ABSTRACT FROM AUTHOR]

A biodegradable matrix with a significant content of bioactive components can be applied for bone tissue replacement, including load-bearing applications in orthopedic surgery. The study outlines the optimized procedure for the production of bioresorbable magnesium-hydroxyapatite (Mg-HA) composites and their corrosion resistance properties. Composites were meticulously crafted by combining pure magnesium with microwave-synthesized hydroxyapatite nanopowder. Sintering occurred via spark plasma sintering technology (SPS). To align the degradation time of the resulting composites with bone remodeling, the corrosion resistance of SPS materials was enhanced through the application of plasma electrolytic oxidation (PEO) and polycaprolactone (PCL) spin-coating methods. The protective properties, morphology dynamics, and composition due to surface treatment and corrosion propagation were investigated using Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic Polarization (PDP), hydrogen evolution tests, Scanning Electron Microscopy (SEM), Energy-dispersive X-ray (EDX) as well as X-ray diffraction (XRD) analysis. Analytics of the physicochemical properties data of the formed coatings indicate a significant improvement in protective characteristics and deceleration of the corrosive degradation of the samples. The application of polycaprolactone to the PEO coating leads to a decrease in the corrosion current compared to uncoated magnesium composites by more than three orders of magnitude: from 1 10−5 to 2 10−9 A cm−2. During long-term exposure of samples to 0.9 % NaCl solution, it was found that coating reduced the rate of corrosion degradation of samples from 1.5 to 80 times compared to an unprotected Mg-HA composite and sintered magnesium. Mg-HA composites treated with PEO exhibit potential application as bioactive and biodegradable materials for orthopedic implants and fixation devices. [ABSTRACT FROM AUTHOR]

Mineral trioxide aggregate (MTA) is widely employed in the field of endodontics, extensively for root canal therapy. Despite being successful, MTA has certain limitations regarding its physico-chemical properties. The present investigation aims to enhance the physicochemical and mechanical behavior of MTA by formulating a cement paste by addition of strontium containing fluorophosphate glass (SrFP). The addition of strontium on to the fluorophosphate glass improves the mechanical strength of the glass network and also accelerates the mineralization process during implantation. In this regard, fluorophosphate glasses with 6 mol% of strontium content were synthesized by standard melt quenching technique and the glasses were ball milled to obtain fine powder. Cement paste was prepared by adding optimized 5 wt% of 6 mol% SrFP glass powder on to 95 wt% of MTA cement. Comparative analysis of conventional MTA with SrFP added MTA were evaluated for various properties such as pH variation, contact angle, radiopacity, compressive strength, push-out bond strength, setting expansion, sealing ability, tooth color change, surface morphology and ALP activity. The obtained results from the investigation exposed that the addition of strontium added fluorophosphate on to MTA impacts the physical properties which includes wettability, sealing ability, push out bond strength and ALP. These findings suggest that SrFP to be a promising additive to MTA with wide scope of applications in dentistry. [ABSTRACT FROM AUTHOR]

This study explores the 3D printing of alginate dialdehyde-gelatin (ADA-GEL) inks incorporating phytotherapeutic agents, such as ferulic acid (FA), and silicate mesoporous bioactive glass nanoparticles (MBGNs) at two different concentrations. 3D scaffolds with bioactive properties suitable for bone tissue engineering (TE) were obtained. The degradation and swelling behaviour of films and 3D printed scaffolds indicated an accelerated trend with increasing MBGN content, while FA appeared to stabilize the samples. Determination of the degree of crosslinking validated the increased stability of hydrogels due to the addition of FA and 0.1% (w/v) MBGNs. The incorporation of MBGNs not only improved the effective moduli and conferred bioactive properties through the formation of hydroxyapatite (HAp) on the surface of ADA-GEL-based samples but also enhanced VEGF-A expression of MC3T3-E1 cells. The beneficial impact of FA and low concentrations of MBGNs in ADA-GEL-based inks for 3D (bio)printing applications was corroborated through various printing experiments, resulting in higher printing resolution, as also confirmed by rheological measurements. Cytocompatibility investigations revealed enhanced MC3T3-E1 cell activity and viability. Furthermore, the presence of mineral phases, as confirmed by an in vitro biomineralization assay, and increased ALP activity after 21 days, attributed to the addition of FA and MBGNs, were demonstrated. Considering the acquired structural and biological properties, along with efficient drug delivery capability, enhanced biological activity, and improved 3D printability, the newly developed inks exhibit promising potential for biofabrication and bone TE. [ABSTRACT FROM AUTHOR]

This study evaluated the osteogenic potential of the bioactive glasses SinGlass (45S5) and SinGlass High (F18) in regenerating critical bone defects in rat calvaria. Both biomaterials promoted new bone formation around the particles, with the SinGlass High (F18) group exhibiting a higher rate of bone maturation. Histomorphological and birefringence analyses revealed better organization of the newly formed bone in the biomaterial-treated groups, and immunohistochemistry indicated the expression of osteogenic markers such as osteocalcin, immunostaining for bone morphogenetic protein 2 (BMP 2), and immunostaining for bone morphogenetic protein 4 (BMP 4). Microtomography computadorized (Micro-CT) revealed centripetal bone formation in both groups, with greater integration of the particles into the surrounding bone tissue. The superior performance of SinGlass High (F18) was attributed to its higher potassium and magnesium content, which enhance osteoconductivity. After 42 days, the SinGlass High (F18) group showed the highest percentage of new bone formation, in line with previous studies. Although our results are promising, the limited follow-up period and use of a single animal model highlight the need for further research to validate clinical applicability. SinGlass High (F18) appears to be a viable alternative to autografts in bone repair, with potential to improve tissue integration and accelerate recovery. [ABSTRACT FROM AUTHOR]

Various pulp-covering materials offer advantages in regenerative root canal treatment, but each has limitations, highlighting the need for more effective antibacterial strategies for pulp repair and regeneration. Mesoporous bioactive glasses (MBG) show significant biological activity, making them valuable in tissue/dental repair. Silver-incorporated MBG exhibits promising antibacterial effects against various bacteria; copper ions are crucial in regulating angiogenesis signals. Co-loading copper and silver in bioactive glasses has been explored to address clinical challenges. This study modified the preparation of silver-copper bimetallic mesoporous bioactive glass, analyzing their textural properties and antibacterial activity against Enterococcus faecalis. The silver-copper co-loaded bioactive glass (designated as AgCu/80S) was synthesized using a sol–gel technique with modifications. Textural analyses were carried out via X-ray diffraction, UV–Vis spectroscopy, Brunauer–Emmett–Teller analysis, and transmission electron microscope. The ion-releasing activity determined using inductively coupled plasma-mass spectrometry, and the antibacterial activity against E. faecalis was assessed through disk diffusion and kinetic bacterial growth curve. The modification led to weaker crystallization of calcium silicate, altering ion-releasing and antibacterial activities. Ag3Cu2/80S exhibited the highest released silver ion concentration at 112.6 ppm, with an inhibition zone of 9.09 ± 0.09 mm in disk diffusion assays. However, the inhibition zone of Ag2Cu3/80S was 9.92 ± 0.04 mm, implying that the antibacterial activity may not only be influenced by silver ions. The AgCu/80S showed a potential antibacterial activity against E. faecalis , whereas further research on AgCu/80S glasses is necessary to optimize ion release conditions, assess bioactivities, and explore potential dental applications. [ABSTRACT FROM AUTHOR]

Background: Teeth with small to moderate cavities can be repaired with enamel resin infiltrants, a form of dental restorative material. In dental materials, it is standard practice to include several filler particles for experimental use in dental resin infiltrates. The resin's BG particles penetrate the lesion and release ions that combine with saliva to provide a mineral-rich environment that can strengthen enamel and heal. This study aimed to compare resin infiltrants based on three types of bioactive glass materials and investigate the penetration depth, microleakage, and the effect of thermal and chemical aging. Methodology: A triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA)-based experimental resin infiltrate was prepared. Initial mixing was done manually for 1 h at room temperature, followed by another mix for 30 min on a magnetic stirrer. This prepared resin, called "PURE RESIN" was then further incorporated with three different types of bioactive glasses, i.e., Bioglass (45S5), boron-substituted (B-BG), and fluoride-substituted (F-BG). Initial manual mixing for 1 h, followed by ultrasonic mixing for 3 min and then proceeded for the final mixing on a magnetic stirrer for 24 h in a dark room at ambient temperature. Human-extracted teeth were demineralized, and the experimental resins were infiltrated on the demineralized surface. The surface area, pore size, and volume of the demineralized surface were measured. The microleakage and penetration depth were analyzed with the stereomicroscope and micro-CT, respectively. The samples were challenged with the pH cycle for 14 days, followed by a scanning electron microscope (SEM). Thermocycling (5,000 cycles) and chemical aging (4 weeks) were conducted, followed by microhardness, surface roughness, and SEM analyses. Statistical analyses were conducted after each test. Results: The F-BG group achieved the highest initial and day 14 penetration coefficients. There was a superior dye penetration with the microleakage analysis in the F-BG group. The 45S5 group had the highest average penetration depth via micro-CT analysis. After thermocycling and chemical aging, the micro-hardness was reduced (non-significantly) among all samples except the F-BG group in post-chemical aging analysis, whereas the surface roughness was significantly increased. SEM images showed the presence of micro-pits on the surfaces after the thermal and chemical aging. Conclusion: The F-BG group achieved the highest initial and day 14 penetration coefficients. There was a superior dye penetration with the microleakage analysis in the F-BG group. The 45S5 group had the highest average penetration depth via micro-CT analysis. After thermocycling and chemical aging, the micro-hardness was reduced (non-significantly) among all samples except the F-BG group in post-chemical aging analysis, whereas the surface roughness was significantly increased. SEM images showed the presence of micro-pits on the surfaces after the thermal and chemical aging. [ABSTRACT FROM AUTHOR]

This research aims to evaluate the efficiency of cavitary varnishes containing experimental bioglasses in the occlusion of dentinal tubules. One hundred and sixty-eight cervical buccal dentin samples were obtained from bovine teeth. Samples were randomized into the following groups: I. Distilled Water (DW); II. Cavity Varnish (CV); III. Colgate® Sensitive Pro-Relief™ (CS); IV. 45S5 Bioglass (45S5); V. KSr Bioglass strontium potassium (KSr); VI. P Bioglass phosphorus (P); and VII. PSi Bioglass phosphorus silica (PSi). The treatments were applied to the surfaces of the samples, which were then subjected to simulated brushing. The samples were analyzed for a) characterization of bioactive glasses; b) surface roughness; c) descriptive analysis of the dentin surface; d) total versus occluded number of dentinal tubules; e) diameter of the dentinal tubules; f) chemical composition of the dentin surfaces, and g) dentin permeability. All groups treated with biomaterials without the brushing challenge showed an increase in roughness and (total or partial) occlusion of the dentinal tubules. The PSi group had the best values for occlusion, while the KSr group had the highest calcium and phosphorus concentrations. After the brushing challenge the roughness was controlled by the presence of biomaterials; 45S5, KSr, and PSi showed occlusion of the dentin tubules. All bioactive glasses showed reduced tooth permeability compared to distilled water. The PSi group had the smallest tubule diameter and highest phosphorus concentration. KSr and PSi bioglasses are promising materials for dentin occlusion and remineralization and are promising new biomaterials for the treatment of dentin hypersensitivity. [ABSTRACT FROM AUTHOR]

Introduction: Calcium hydroxide (Ca(OH)2) is the most commonly used medicament in endodontics. This study aimed to investigate the effect of bioactive glass (BG) use with or without Ca(OH)2 on the biological and mechanical properties of dentin. Materials and Methods: Standard holes were created to simulate root canals on 84 dentin slices. Four groups were formed according to the medicament placed in the root canals: Ca(OH)2; Ca(OH)2 + 7% BG; BG and control. Scanning electron microscopy analysis to evaluate the dentin surfaces exposed to the test medicaments and energy dispersive X-ray analysis to observe apatite formation were used on the 1st, 7th, and 14th days. X-ray diffraction measurements were performed to investigate mineral phase formation. Microhardness and pH measurements were also carried out. Data were analyzed using Kruskal–Wallis and Wilcoxon signed-rank tests (P < 0.05). Results: The Ca(OH)2 and control groups showed the highest Ca and P mineral content on the 14th day, whereas the lowest Ca and P content was found in the Ca(OH)2 + BG group (P < 0.05). A gradual decrease in crystal formation was found in the Ca(OH)2 + BG group from the 1st day to the 14th day. The highest microhardness measurements were also recorded in the Ca(OH)2 + BG group (P < 0.05). The Ca(OH)2 + BG group showed the highest pH measurements (P = 0.001). Conclusions: Ca(OH)2 + BG can be an alternative intracanal medicament. Further studies should be performed to determine the clinical implications of this combination. [ABSTRACT FROM AUTHOR]

To overcome limitations of dentin bonding due to collagen degradation at a bonded interface, incorporating bioactive glass (BAG) into dentin adhesives has been proposed to enhance remineralization and improve bonding durability. This study evaluated sol–gel-derived BAGs (BAG79, BAG87, BAG91, and BAG79F) and conventional melt-quenched BAG (BAG45) incorporated into dentin adhesive to assess their remineralization and mechanical properties. The BAGs were characterized by using field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy for surface morphology. The surface area was measured by the Brunauer–Emmett–Teller method. X-ray diffraction (XRD) analysis was performed to determine the crystalline structure of the BAGs. Adhesive surface analysis was performed after approximating each experimental dentin adhesive and demineralized dentin by using FE-SEM. The elastic modulus of the treated dentin was measured after BAG-containing dentin adhesive application. The sol–gel-derived BAGs exhibited larger surface areas (by 400–600 times) than conventional BAG, with BAG87 displaying the largest surface area. XRD analysis indicated more pronounced and rapid formation of hydroxyapatite in the sol–gel BAGs. Dentin with BAG87-containing adhesive exhibited the highest elastic modulus. The incorporation of sol–gel-derived BAGs, especially BAG87, into dentin adhesives enhances the remineralization and mechanical properties of adhesive–dentin interfaces. [ABSTRACT FROM AUTHOR]

Bone tissue engineering has emerged as an innovative approach for repairing and regenerating bone defects. This study focuses on the development of new scaffolds with key attributes, including biocompatibility, bioactivity, biodegradability, cost effectiveness, and safety. In this investigation, we designed and synthesized a novel nanofibrous scaffold using the electrospinning method, incorporating zein/58S bioactive glass. The manufactured scaffolds underwent comprehensive characterization for morphology, sustainability, and chemical structure. Moreover, to demonstrate their efficacy in bone healing, we quantified essential factors such as biodegradation rate, contact angle, mechanical strength, bioactivity, cytotoxicity, and cell adherence. Following that, the osteogenesis effect of scaffolds was evaluated in vitro as well as in vivo through implanting them in the calvarium of the rats. Specifically, we conducted detailed investigations using alizarin red staining, real-time PCR, and histopathology, along with immunohistochemistry assessments. Based on our results, the fiber diameters were about 160.2 ± 7 nm, 163.5 ± 38.3 nm, and 164 ± 39.3 nm, respectively for zein, 2%BG, and 4%BG mats. Incorporation of 58 S increased contact angle from 96.03 ± 0.7° to 51.7 ± 2.02°, and consequently improved cell adhesion. The degradation rate of all scaffolds was about 20%, and chemical analysis (FTIR) confirmed the presence of 58 S in zein nanoscale mats. Tensile analysis presented that applying bioactive glass rescued Young's modulus from 0.34 ± 0.07 to 0.08 ± 0.009 MPa. Meanwhile, other results revealed that 4%BG scaffolds exhibit desirable properties, being porous, safe, bioactive, and osteogenic. These findings robustly affirm the competence and potential of the manufactured nanofibrous scaffold containing 4%BG for applications in bone tissue engineering. The schematic diagram illustrating different stages of the study, including; zein/BG scaffold synthesis, characterizations and osteogenesis evaluation in vitro and in vivo [ABSTRACT FROM AUTHOR]

Background/Objectives: Air particle abrasion (APA) is a common surface preparation method in dentistry, particularly for improving bond strength to dentin. This review evaluates the influence of APA on dentin adhesion. Methods: A systematic literature search from 2018 to 2023 was conducted according to PRISMA-ScR guidelines. Articles investigating the effects of APA on dentin adhesion using different particle types, sizes and adhesive systems were included. Data extraction included particle size, air pressure, outcomes tested and failure modes. Results: Fourteen primary studies met the criteria. Bioactive glass showed higher bond strength and more cohesive failures than alumina. Alumina particles (50 μm) bonded effectively in etch-and-rinse adhesive systems but failed more often in self-etch systems. Silica-modified alumina and mixed abrasive systems showed improvements in bonding performance. Optimal APA parameters were identified as 50 μm particle size, 60 psi (4 bar) air pressure and 5 s exposure time. Longer exposure times provided no additional benefit. Self-etch systems showed reduced bond strength compared to etch-and-rinse systems. Conclusions: This review looks at how particle type, size and air pressure affect dentin adhesion. Bioactive glass is a superior material due to its bond strength and reduced cytotoxicity. The optimal APA parameters are 50 μm particle size, 60 psi and 5 s. Etch-and-rinse systems are recommended for optimal adhesion. Further research is required on APA protocols and long-term durability. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of the substitution of CaO by SrO on the structure, degradation and in vitro apatite formation of sol–gel-derived bioactive glasses with composition of 58SiO 2 – (38- x)CaO – x SrO – 4P 2 O 5 , where x varies between 0 and 10 mol.%. The IV-type nitrogen adsorption/desorption isotherms and pore size values (ranging from 5.41 to 12.56 nm) confirmed the mesoporous structure of the synthesized glasses. The detailed structural analysis was carried out by X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). As network modifiers, the addition of Ca and Sr oxides disrupted the bonds of bridging oxygens (BOs) and resulted in the formation of non-bridging oxygens (NBOs), where the substitution of Ca with Sr led to an increase in Q 1 units and a decrease in Q 3 units. The effects of the addition of Sr on sample degradation and apatite formation were assessed using an assay in tris-(hydroxymethyl)-aminomethane and hydrochloric acid (Tris–HCl) and simulated body fluid (SBF). The results demonstrated that the substitution of CaO by SrO in the CaO – SiO 2 – P 2 O 5 bioglass system altered the glass structure, resulting in reduced sample degradation and delayed apatite formation. This suggests that the incorporation of Sr into bioactive glasses may serve as a promising strategy to regulate the structure, dissolution behavior and apatite formation of silicate-based glasses, particularly concerning their long-term applications within the human body. [ABSTRACT FROM AUTHOR]

In this study, we present novel, vitrimeric and biobased scaffolds that are designed for hard tissue applications, composed of acrylated, epoxidized soybean oil (AESO) and reinforced with bioactive glass that is Tellurium doped (BG-Te) and BG-Te silanized, to tune the mechanical and antibacterial properties. The manufacture's method consisted of a DLP 3D-printing method, enabling precise resolution and the possibility to manufacture a hollow and complex structure. The resin formulation was optimized with a biobased, reactive diluent to adjust the viscosity for an optimal 3D-printing process. The in vitro biological evaluation of the 3D-printed scaffolds, combined with BG-Te and BG-Te-Sil, showed that the sample's surfaces remained safe for hBMSCs' attachment and proliferation. The number of S. aureus that adhered to the BG-Te was 87% and 54% lower than on the pristine (control) and BG-Te-Sil, respectively, with the eradication of microbiofilm aggregates. This work highlights the effect of the vitrimeric polymer matrix and doped, bioactive glass in manufacturing biocompatible, biobased, and antibacterial scaffold used in hard tissue application. [ABSTRACT FROM AUTHOR]

The document "Advances in Nanocomposites: Preparation, Characterization, Properties, and Applications" published in the journal Molecules discusses the development and applications of nanocomposite materials. Various studies highlighted in the document focus on the preparation, characterization, and applications of nanocomposites in areas such as food packaging, tissue engineering, and catalytic activity. Researchers have explored the use of nanocomposites in creating materials with multifunctional properties, such as improved mechanical strength, electrical conductivity, and barrier characteristics. The document emphasizes the growing research area of nanocomposites and their promising applications in diverse sectors. [Extracted from the article]

Three-dimensional (3D) porous scaffolds based on polycaprolactone (PCL)/chitosan (CS)/bioactive glass (BG) nanoparticle composites were fabricated by the freeze-drying technique for bone tissue engineering. The physiochemical properties of the developed PCL/CS/BG scaffolds were studied using FTIR, XRD, EDX and SEM. Furthermore, the swelling degree, porosity, water retention ability, compression strength, in vitro biodegradation, bioactivity and biocompatibility of the scaffolds were examined. The PCL/CS/BG scaffolds with 4 wt. % of BG content presented adequate pore size (106 μm), porosity (156%), water swelling degree (128%), water retention ability (179%), compressive strength (3.7 MPa) and controlled degradation behavior, which could be ideal for bone tissue engineering. The PCL/CS/BG composite scaffolds showed good antimicrobial activity against both test bacteria and fungi. The MTT assay demonstrated the biocompatibility of PCL/CS/BG scaffolds against C3H10T1/2 cell line. The Alizarin red staining assay confirmed the osteogenic activity of the PCL/CS/BG scaffolds. [ABSTRACT FROM AUTHOR]

The development of new bioactive glasses (BGs) with enhanced bioactivity and improved resistance to crystallization is crucial for overcoming the main challenges faced by commercial BGs. Most shaping processes require thermal treatments, which can induce partial crystallization, negatively impacting the biological and mechanical properties of the final product. In this study, we present a novel bioactive glass composition, S53P4_MSK, produced by a melt–quench route. This novel composition includes magnesium and strontium, known for their therapeutic effects, and potassium, recognized for improving the thermal properties of bioactive glasses. The thermal properties were investigated through differential thermal analysis, heating microscopy and sintering tests from 600 °C to 900 °C. These characterizations, combined with X-ray diffraction analysis, demonstrated the high sinterability without crystallization of S53P4_MSK, effectively mitigating related issues. The mechanical properties—elastic modulus, hardness and fracture toughness—were evaluated on the sintered sample by micro-indentation, showing high elastic modulus and hardness. The bioactivity of the novel BG was assessed following Kokubo's protocol and confirmed by scanning electron microscopy, X-ray energy dispersive spectroscopy, and Raman spectroscopy. The novel bioactive glass composition has shown high sinterability without crystallization at 700 °C, along with good mechanical properties and bioactivity. [ABSTRACT FROM AUTHOR]

In this work, the bioactive glasses are derived from biowaste resources such as corn husk ash, sugarcane leaves ashes, and eggshell powder via the melt quench method. The raw materials were melted in a platinum rhodium crucible at 1550 °C, followed by rapid cooling to obtain a glassy phase. In order to assess the in-vitro bioactivity, glasses were soaked in simulated body fluid at 37 °C for different time durations, i.e., 7,14, 21, and 28 days. Biocompatibility of these glasses was also tested on MG-63 cell lines using a 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl tetrazolium bromide (MTT) assay test. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) were used to analyze the hydroxyapatite (HAp) layer formation and the thermal stability of soaked samples. SEM micrographs showed the cauliflower and flakes type morphology of hydroxyapatite (HAp) on the glass surfaces after 7 days of soaking in SBF. The EDS analysis also confirmed the formation of a hydroxyapatite layer with a Ca/P ratio that varies from 1.6 to 3.9. MTT assay revealed the biocompatibility for different dosages (1, 2, 5, and 10 mg/ml) of the as-prepared glasses with MG-63 cell lines. The heat treatment of soaked glasses converts the amorphous HAp layer into a crystalline HAp layer, followed by its conversion in stable diopside as main and Ca 2.589 Mg 0.41 (PO 4) 2 as minor phase. The tested glasses exhibited good bioactivity and biocompatibility particularly higher CaO content glass, suggesting for use in bone regeneration applications. [ABSTRACT FROM AUTHOR]

Borate bioactive glasses (BBGs) constitute the recently produced bioactive glasses (BGs) in the domain of bioactive materials, offering enhanced functionalities over conventional silicate and phosphate BGs. This advancement is primarily characterized by BBGs' rapid yet controllable degradation rates, superior bioactivity, and the ability to swiftly form a hydroxyapatite layer (HAP) upon interaction with physiological fluids. A distinguishing feature of BBGs lies in their customizability; doping with therapeutic metal ions tailors their bioactivity towards specific physiological responses, including promoting angiogenesis, antibacterial activity, and osteogenesis. This versatility of BBGs' applications extends to bone regeneration, wound healing, drug delivery systems, and potentially nerve regeneration. The emergence of BBGs marks a significant milestone in biomaterials research, setting new standards for the development of regenerative treatments and opening new avenues for medical applications. This literature review provides a comprehensive examination of BBGs, discussing their evolution, properties, clinical applications, comparative advantages, and future directions. [ABSTRACT FROM AUTHOR]

This study investigates the effects of Mn-Zn ferrite (MZF) content and heat treatment temperature on the structural, mechanical, magnetic, and bioactive properties of Na 2 O-CaO-P 2 O 5 glass ceramics. Various MZF contents (5MZF, 10MZF, 20MZF, and 40MZF) were incorporated into the glass ceramics and subjected to heat treatment at different temperatures (600, 650, 700, and 800 °C). The results demonstrated that increasing the MZF content significantly enhanced the mechanical properties, including Vickers hardness, Knoop hardness, and Young's modulus. For example, the Vickers hardness values increased from 5.6 GPa in 5MZF samples to 7.1 GPa in 40MZF samples. X-ray diffraction analysis revealed the presence of major crystalline phases, such as Ca 2 P 2 O 7 and Na 4 Ca(PO 3) 6 , with NaFe 3 P 3 O 12 and (Zn,Mn)Fe 2 O 4 appearing in samples with higher MZF content. Magnetic measurements indicated that the 40MZF samples treated at 700 °C reached a satisfactory hyperthermia temperature of 43 °C within 16 min. Bioactivity tests showed a decrease in bioactivity with increasing MZF content, whereas cytotoxicity assays confirmed that all MZF-Na 2 O-CaO-P 2 O 5 bioactive glass ceramics were non-toxic, maintaining over 100 % cell viability after 24 h. These findings suggest that MZF-containing glass ceramics have potential applications in the biomedical field, particularly when enhanced mechanical and magnetic properties are required. [ABSTRACT FROM AUTHOR]

Bioactive glasses (BGs) have emerged as invaluable resources for bone tissue engineering due to their remarkable properties such as bioactivity, resorbability, cell compatibility, and osteoconductivity. However, these materials exhibit certain limitations when subjected to high temperatures, for their tendency to crystallize, thus leading to diminished bioactivity, reduced mechanical strength, and altered dissolution kinetics. One promising approach to counteract this problem is to reduce the alkaline element content in BGs while simultaneously adding strontium and magnesium. Building on previous studies of Bio_MS, a recently developed experimental formulation, we investigated the contributions of strontium and magnesium to the thermal, mechanical, and biological properties of various bioactive glasses, including commercially available options. Differential thermal analysis, heating microscopy, X-ray diffractometry, environmental scanning electron microscopy, measurement of the Young's modulus, simulated body fluid testing, cytotoxicity tests, cell viability, growth, adhesion and morphology were assessed through an integrated approach and compared for a complete evaluation of BGs, and of doped BGs, also undergoing thermal treatments. The results demonstrated improved thermal, mechanical and biological behaviors of the magnesium-strontium-doped BGs, thus paving the way for the development of BGs with enhanced biomedical perspectives. [ABSTRACT FROM AUTHOR]

Cutting-edge photonic devices frequently rely on microparticle components to focus and manipulate light. Conventional methods used to produce these microparticle components frequently offer limited control of their structural properties or require low-throughput nanofabrication of more complex structures. Here, we employ a synthetic biology approach to produce environmentally friendly, living microlenses with tunable structural properties. We engineered Escherichia coli bacteria to display the silica biomineralization enzyme silicatein from aquatic sea sponges. Our silicatein-expressing bacteria can self-assemble a shell of polysilicate "bioglass" around themselves. Remarkably, the polysilicate-encapsulated bacteria can focus light into intense nanojets that are nearly an order of magnitude brighter than unmodified bacteria. Polysilicate-encapsulated bacteria are metabolically active for up to 4 mo, potentially allowing them to sense and respond to stimuli over time. Our data demonstrate that synthetic biology offers a pathway for producing inexpensive and durable photonic components that exhibit unique optical properties. [ABSTRACT FROM AUTHOR]

Hemostatic materials used in penetrating injuries or incompressible wounds must possess exceptional efficacy in preventing bleeding. In this study, mesoporous bioglass (MBG) was synthesized using a two‐step acid‐catalyzed self‐assembly method, and a novel hemostatic sponge (MBG/CH/GEL) was prepared by combining chitosan (CH), gelatin (GEL), and MBG using a freeze‐drying method. The characteristics and hemostatic effects of the MBG/CH/GEL composite hemostatic sponge were analyzed and evaluated. Research has shown that the high specific surface area of MBG (730 m2/g) provides more blood cell adhesion sites during hemostasis, resulting in a low hemolysis rate, favorable swelling rate, and porosity of the hemostatic sponge. Additionally, MBG can release Si4+ and Ca2+ ions during hemostasis, giving the composite hemostatic sponge excellent cell compatibility and promoting cell growth. Compared with commercially available gelatin hemostatic sponges, it cannot only quickly stop bleeding but also has a greater compressive strength (212.07 kPa) and adhesion strength (11.54 ± 0.16 kPa), making it suitable for use in hemostasis of incompressible wounds. Furthermore, the composite hemostatic sponge exhibited significant antibacterial effects against Staphylococcus aureus and Escherichia coli. These results indicate that the MBG/CH/GEL composite hemostatic sponge, which is a hemostatic material, has promising applications. [ABSTRACT FROM AUTHOR]

There have been remarkable advancements in regenerative medicine for bone regeneration, tackling the worldwide health concern of tissue loss. Tissue engineering uses the body's natural capabilities and applies biomaterials and bioactive molecules to replace damaged or lost tissues and restore their functionality. While synthetic ceramics have overcome some challenges associated with allografts and xenografts, they still need essential growth factors and biomolecules. Combining ceramics and bioactive molecules, such as peptides derived from biological motifs of vital proteins, is the most effective approach to achieve optimal bone regeneration. These bioactive peptides induce various cellular processes and modify scaffold properties by mimicking the function of natural osteogenic, angiogenic and antibacterial biomolecules. The present review aims to consolidate the latest and most pertinent information on the advancements in bioactive peptides, including angiogenic, osteogenic, antimicrobial, and self-assembling peptide nanofibers for bone tissue regeneration, elucidating their biological effects and potential clinical implications. [ABSTRACT FROM AUTHOR]

Highlights In bone tissue engineering, polycaprolactone (PCL) has been extensively employed as a bone substitute due to its good biocompatibility, outstanding mechanical properties, controllable degradation rate, and excellent processability. However, PCL is a bioinert polymer with poor hydrophilicity, and it fails to actively induce new bone formation after implantation into the lesion. Therefore, it is generally necessary to find a bioactive material to improve these deficiencies of PCL. In this study, we first prepared a silicate‐based bioactive glass (SBG, 48SiO2‐24Na2O‐24CaO‐4P2O5, in mol%) using the melt‐quenching method, and then fabricated a series of PCL/SBG composite scaffolds with varying SBG powder contents (0, 10, 20, 30, and 40 wt.%) by 3D fiber deposition. The physico‐mechanical properties, mineralization capability, degradability and biological behavior of PCL/SBG scaffolds were systematically characterized. The results showed that the contact angle of the scaffolds decreased from 121.90 ± 3.74° to 86.29 ± 3.46° with the increase of SBG content, implying that the hydrophilicity was improved, and meanwhile the porosity and mechanical strength of PCL/SBG scaffolds first increased and then decreased, but they were within the range of human cancellous bone. Additionally, the degradation rate of PCL/SBG groups can be regulated by adjusting the SBG content. Finally, compared to the pure PCL group, the cell viability and alkaline phosphatase activity of MC3T3‐E1 on PCL/SBG groups were significantly enhanced. In the present work, the PCL/30SBG group exhibited great potential as a viable alternative to autografts and offers promising clinical applications for bone defect repair in the future. The addition of SBG powders accelerates the degradation of PCL. The addition of SBG powders enhances the hydrophilicity of PCL scaffolds. The degradation rate and bioactivity of PCL/SBG scaffolds can be regulated. The mechanical strength is within the range of human cancellous bone. PCL/30SBG shows improved cell viability and ALP activity. [ABSTRACT FROM AUTHOR]

This study determines the possibilities of synthesis of porous glass-ceramic materials based on Bioglass 45S5 using different methods obtained porous materials. In this work used foaming with sintering method for the set: bioglass 45S5 + glass cullet (CRT) + glass water (WG) and method sintering with forming-pore agents for the: bioglass + glass water (WG) + dried banana peels. The sets were melting and the next step sintering process. The resulting foams were examined and analysed for structural, microstructural, and physical properties. The research allowed for a quantitative and qualitative assessment of the foaming process generated by the presence of WG with the addition of CRT cullet and WG together with dried banana peel. It was found that WG with the addition of CRT cullet was a solution that offered the possibility of obtaining a large number of evenly distributed pores and higher total porosity compared the second set (WG + banana peel). Moreover, the use of CRT cullet and banana peel allowed the introduction of biogenic elements such as strontium, barium and potassium into the obtained materials, which have a positive effect on the stimulation of osteogenesis. [ABSTRACT FROM AUTHOR]

Bioactive glass (BG-45S5) production through the melting process is affected by a wide variety of parameters. This study investigated the synthesis of BG-45S5 granules and the process variables to produce a bioactive and osteoinductive BG for bone grafting applications. The melting process was initially analyzed by varying parameters such as crucible type and pouring environment using P 2 O 5 as phosphorus precursor. The obtained products were characterized by crystalline phases, characteristic chemical groups, particle size distribution, and chemical composition. Materials poured into graphite or steel molds resulted in particle sizes more suitable for applications in granular form. Using a platinum crucible yielded a chemical composition closer to the target when compared with another ceramic crucible. Subsequently, the melting process was evaluated to different phosphorus precursor (P 2 O 5 or Na 2 HPO 4) and melting duration (1 or 2 h) in a platinum crucible verifying their effects on the thermal behavior, chemical composition and structure of BG-45S5. Employing Na 2 HPO 4 as a precursor led to higher glass transition and crystallization temperatures as compared to P 2 O 5 , enhancing glass homogeneity and structural stability. The product with better characteristics in terms of composition and structure was further characterized for bioactivity and cell culture behavior, showing a greater amount of mineralization nodules when compared to commercial hydroxyapatite. This is particularly due to its behavior as the solubility and interaction in biological environments. [ABSTRACT FROM AUTHOR]